In the following circuit,the reading in the ammeter is (in $mA$)

$A$ potential barrier of $0.4 \,V$ exists across a p-n junction. An electron enters the junction from the $n$-side with a speed of $6.0 \times 10^{5} \,ms^{-1}$. The speed with which the electron enters the $p$-side will be $\frac{x}{3} \times 10^{5} \,ms^{-1}$. The value of $x$ is ..............
(Given: mass of electron $= 9 \times 10^{-31} \,kg$,charge on electron $= 1.6 \times 10^{-19} \,C$.)

What is the value of the current through the diode in the given circuit (in $\text{ mA}$)?

When no bias is applied to a $P-N$ junction,the current is:

If no external voltage is applied across a $P-N$ junction,there would be:

The current through the ammeter (neglecting internal resistance) in the following circuit is